Character Role Analysis
The Chorus plays the role of information tool at several occasions in the play; perhaps most notably when they fill Orestes in on the horrible dream of Clytemnestra, which encourages him in his quest for revenge. The Chorus also becomes a misinformation tool when they convince the Nurse to distort the message she's bringing to Aegisthus. That said, because we, the readers, know the real truth of the matter – that the Chorus is doing this to help out Orestes – it might be better to think of the Chorus acting as a "Companion" at this point. This just goes to show that the Chorus plays a very complicated role in any Aeschylean tragedy, and can't always be boiled down to one simple role.